Hydraulic device for opening and closing filter presses and other pressure-applying mechanisms



Aprllls, 1933. E. RAYMOND 1,904,531

HYDRAULIC DEVICE FOR OPENING AND CLOSING FILTER PRESSES AND. OTHER PRESSURE APPLYING MECHANISMS Filed July 9, 1927 3 Sheets-Sheet 1 Apnl 18, 1933. T. E RAYMOND 1,904,531

HYDRAULIC DEVICE FOR OPENING AND CLOSING FILTER PRESSES AND OTHER PRESSURE APPLYING MECHANISMS Filed July 9, 1927 .3 Sheets-Sheet 2 Apnl l8, 1 933. Y T RAYMOND 1,904,531

HYDRAULIC DEVICE FOR OPENING AND CLOSING FILTER PRESSES AND OTHER PRESSURE APPLYING MECHANISMS Filed July 9, 1927 3 Sheets-Sheet 5 INVENT N y ,Q

\\BYU m 1/ ATTORNEY Patented Apr. 18, 1933 UNITED; STATES I,

PATENT oaret:

THOMAS E. RAYMOND, '01 ZAN'ESVILLE, OHIO, ASSIGNOR '1'0 SIMPLEX .GOMIfANY, A. CORPORATION OF OHIO mnaunc nnvrcn m ormrme crosme FlZLTER mess AND OTHER rnnssunz-arrtme unonamsms Application filed July 9, 1927. Serial No. 204,588.

This invention relates to improvements in hydraulic device for closing and opening filter presses and other pressure-applying mechamsms.

The principalobjec-ts of this invention are for closing the press by liquid pressureand of a screw ram for positively retaining the press in closed position by screw action; to provide a construction whereby control of the projection or extension and retraction of the .ram is centralized in a single speed lever; to

provide means whereby the valves of 'a hydraulic pump may be caused to assume four different relative positions for the purpose of 1) rapid low pressure projection of the ram, (2) sloufiprojection at high pressure, (3) a neutral position and 4) a'rapid retraction of the ram; to provlde in a device of the character specified, a valve which is free to seat in either one of two directions and which will continuousl prevent liquid from passing in either direction so long as the valve is unrestrained and which may be restrained to pass liquid continuously in one direction or in both directions and can be positively closed in one direction to prevent liquid under pressure passing from either di- 'rection;to provide a hydraulic closing and opening device comprising a ram and handoperated pump in a single, compact unit that :y-nzay be readily and quickly substituted for the screw in conventional screw-closed presses and will, when applied to a press form a unitary, ptirtithereof; to provide a unitary {v :liydraulic ram and hand-o erated pump which "may be's-upported entlrely from the frame ofthe filter press; to prpvide a construction in which the-ram cylinder and pump casing are screwed together preferably a about an axis common to the ram cylinder and piston chamber of the pump, and in which the operation of screwing the pump to the ram cylinder will cause a hydraulic tight connection to be made; to provide a device which may be assembled and mounted from opposite endsof a conventional round hole in the frame of a filter press; which when applied as an attachment to existing presses will be clamped rigidly to the frame, and will be mounted bya squeezing pressure be-' tween members of the attachment parts against opposite sides of the supporting frame; to arrange the hand-pump lever in a position which will not permit the weight of the operator to be applied thereto; to arrange the mechanical parts in a device of the character specified to causev the hand-operated pump lever to be operated at an angle of inclination to an axis passing through the central line of the ram and preferably to cause the pump-operating lever to be ivoted adjacent to the-axis of the ram an pump piston.

With these and other objects in view, the

invention comprises the combination of members and arrangement of parts so combined as to co-act and cooperatewith each other in the performance of the functions and the accomplishment of the results herein contemplated, and comprises in one ofits adaptations the species or preferred form illustrated in the accompanylng drawings, in which Fig. 1.is a view, in side elevation partially broken away, of a filter press having mounted on the front frame part, an opening and closing device embodying my invention;

Fig. 2 is a vertical section through the axes 'of.the ram-cylinder and pump casing showing the ram in retracted position, the pump lever in perpendicular position, and the speed lever at a low position; i

' Fig. 3 is an enlarged section similar to Fig. 2 showing the speed lever in reverse position and the pump lever in an inclined position; I

Fig. 4 is a diagrammatic view showing the four positions of the speed lever; and

Fig. 5 is a fragmentary section similar to Fig. 3, showing' the position of the valves when the speed lever is moved to neutral position.

Referring now to these drawings, which illustrate a preferred embodiment of my invention, P indicates the press as a whole which is composed of the conventional front and rear heads H, H and intermediate filter plates and frames all mounted on the side bars B which are supported at the front by the front frame member F and at the rear by the head H and rear frame F.

In accordance with my invention, a preferred form of which is illustrated in the ac- .companying drawings, my hydraulic opening and closing device is mounted on the front frame member F of the filter press, and' in the embodiment shown, comprises an attachment which has been substituted for the conventional screw closing device and is mounted in the front frame aperture usually provided for such screw-closing devices.

By the use of my invention, my opening and closing device embodies two separable main parts which when assembled are rigidly connected together to form a unitary structure and comprises a'ram-cylinder 1 and pump casing 2, which are connected together end to end. One of these members is preferably provided with an external screwthread and the other with an internal screwthread and in assembly the two ends are screwed together. As shown, the ram-cylinder 1 is provided at one end with an open ram chamber or bore 1 containing a ram 7 and at the opposite end has an integral housing 1' provided with a housing bore 1 opening in the opposite direction from the ram bore and adapted to receive a connection nipple 4 and a portion of a pump block 3. Said two oppositely-extending bores are separated by a partition 1 having a liquid-passing channel 1 which is preferably centrally-disposed as illustrated. The pump block 3 is in axial alignment with the ram-cylinder and the forward end-of said pump block 3 is provided with the connection nipple 4 which has an axial channel 4 and initially has an air and liquid-tight connection at one end 4: with the pump mechanism, being screwed into the block 3, while the other end 4 fits into a bore or depression 1 formed in the rear end of the partition 1 of the ram-cylinder 1. The pump casing 2 is provided, as illustrated,

' with an externally screw-threaded socket portion 2 which screws on over the rearwardlyprojecting housing of the ram-cylinder 1 and the pump block 3 extends within the bore 1 in the said housing, in the ram-cylinder. The P ram-cylinder at its rear end is provided with a suitable collar 1*, and in mounting, the housing end is passed from the rear of the frame member F through the aperture f therein, the

. said cylinder is suitably held against turning,

and the end 2' of the pump casing is screwed thereon thus producing a tight joint between the forward end of the pump block and the end of the ram chamber, a gasket 5 being provided which is compressed by the screwing together of said two main parts to produce a hydraulic-tight joint.

'lnorder to rigidly mount my closing and openlng device on the frame, I preferably clamp the frame of the press between the said two parts of my closing and opening device,

a squeezing pressure to be exerted between the collar 1" and the end 2 of the pump casing 2 which will thus clamp the housing or enclosing parts rigidly to the frame F.

The ram 7 is mounted to slide within said bore or ram-compartment 1 and has at its rear end means for producing an air and liquid-tight joint with the walls of the ram chamber and, as shown, the rear end of the ram is provided with cupped gaskets 7, 7 which, as shown, are securely held in place on the end of the ram by a nut 7 threaded on a projection 7 the two gaskets having a compressible washer '7 arranged between the same.

In the said preferred form of my invention,

I provide novel pumping mechanism which not only causes the projection of the ram first rapidly and then slowly at high pressure to close the press, but also utilizes thesame pumping mechanism to retract or withdraw the ram to open the press. I preferably in the usual way project the ram quickly at low pressure until it comes in contact with the press-head or other part on which it is desired to exert pressure and, as shown, until it comes into contact with a thrust block T 3 carried by the press-head. Upon such contact, it provide means for enabling high pressure to be applied to produce a tight closing of the press and when the closing pressure has reached a sufficiently high degree as indicated by an indicator 1, ll utilize novel means which will be hereinafter described for mechanically locking the press in such closed position.

My preferred means for producing the results hereinabove specified comprises a novel arrangement of pistons, valves and valve controlling means which will now be described. As illustrated, I provide a suitable ump block, such as the block 3,'which in the construction shown, is mounted in and projects outwardly from the screw-threaded bore 2 of the pump casing 52, being locked in place therein by a lock washer 2", forward end 3 projecting within the body of and has itsj mount in each of these bores, pistons 12 and 13 respectively which are, as shown, mounted on a common piston rod 14. Said piston rod 14 extends forwardly from the mouth of the bore 10 and is connected within the fluid reservoir of the 'casin with mechanism 7 for reciprocating it. As s own, said rod 14 is connected with a sliding head 15 supported on a shelf 16 and the head 15 is reciprocated by a rock-shaft 17 suitably mounted in the casing 2 and provided at an end which projects beyond the outside of the casing with a socket 18 for a' pump-lever 19, Connected with'the rock-shaft within the casing by a set screw 20 is a rocln'ng-arm 20 having a' knuckle 21 extending into an,a erture 15' in the head 15 sothat upon a roc g of therock-shaft 17, theknuckle moves the head and pistons back and forth in the piston bores.

The arrangement of valves and'controlling means comprises a plurality of parallel valvebores or liquid channels, each of which communicates with a piston bore or chamber and the passage of liquid through which is controlled to enable a retraction-of the ram as well as the projection thereof. Oneof these .channels is provided with a series of valves,

one of which isdouble-acting and movable in opposite directions and closable in one direc-' tlon to permit passage of fluid for projection of the ram, and then to be held closed in the opposite direction against the passage of furt er liquid from the reservoir, while the other passage is provided with a double-acting valve which is seatable in two directions to prevent the passage of liquid during projection 5f the ram and which is controllable or restrainable after the projection of theram to permit withdrawal of liquid from behind the ram so as to create a partial vacuum and thus to withdraw the ram by operation of th orgump.

e piston bores are, as aforesaid, preferably arranged axially in the pump block 3 and I. provide eccentrically and in parallel relationship therewith two fluid channels C, Q, one containing 'a series of three communicating valves'comprising an inlet valve 22, an intermediate valve 23, and an outlet valve 24 respectively, the latter valve being formed in a sleeve or valve casing 24" which is seated in the outer end of an enlarged part 24 of the fluid channel C. 'The' inlet valve 22 is a double-acting valve comprising a valve -head 22' mounted at the rear end of the bore on a stem 22 which extends forwardly through said bore 22 and is provided at its opposite end with a "alve head 22".

The intermediate valve 23 in said passage has at its rear side only a valve head 23' mounted on a stem 23" which extends the full length of the bore and into a position adjacent to the valve head 22'. The outlet valve 24 is provided at its rear end with a valve head 24' mounted in the casing 24 and having a stem projecting within the bore and preferably being arranged to extend into proximity with the valve head 23 for the purpose hereinafter explained. The valve head 24' is normally restrained and held in closed position by a spring 25 abutting said valve at one end and having its other end abutting against a valve plug 26. The liquid channel C communicates at the rear of with the low pressure piston bore and has another transverse channel 27 connecting with the high pressure bore 11 and still another transverse outlet channel 28 communicaiting with the bore of the connecting nipp e 4.

so the inlet valve 22 by a transverse channel 27 The stroke of the valve head 22 is suficiently long that, when seated, it will cause a positive unseating and holding in unseated position of the other valve heads. Thus, the length ofthe stem 22 in relation to the outlet valve channel 22, the position of valve heads thereon and the proximity of the valve stems of the other valve heads to their channels is such that when the valve 22 is fully restrained and forced. into seated position as will be the case in the reverse position shown in Fig. 3, all the other valve stems will be engaged and all the valve heads will be moved ofl' their seats and held in inoperative positions. When however, said valve 22 is unrestrained or partly restrained, one I or more of the other valve heads will be seatable on the seats and operative. Thus, in

the low position shown in Fig. 2, the valve heads 24', 23' and 22' are all capable of seat:

ing, while in the neutral position shown in Fig. 5, valve heads-23' and 22', are positively moved off their seats while the valve'24 is still seated.

The other parallel longitudinal channel C for the withdrawal of liquid frombehind the ram comprises a bore plugged at its rear end with a plug 28' and havingat :ltS forward end a valve 29 rovided with double-acting valve members comprising,

when liquid is being withdrawn from behindv and valve heads-being arranged in relation to the bore to permit a seating in opposite directions when unrestrained so as to cooperate with the series of valves in thechannel C during the projection of the ram and when restrained to permit seating in one direction only to permit passing of liquid coming from behind the ram to-the reservoir but to prethe valves as hereinafter described by the operation of a speed lever 32 connected to a vertical shaft 33 suitably mounted in the casing 2 and having at its lower end an eccentric or cam member 34, adapted, upon movement of the speed lever 32, to engage the controlling sleeve to move it into contact with the valves.

In starting, when the speed lever is at low position, the valve head 24 is normal- 1y held in closed position by the pressure of the spring 25, as aforesaid, the valve head 23' is free to seat and in the double-acting valve at the inlet, the valve head 22' is likewise free to seat while the opposite valve head 22 on the stem 22 will, because of the proximity of its stem to the other valve stems 23, 24*, the latter of which is held by spring 25, and the distance from its seat of the valve head 22*, be held in open position. These three valve heads 24, 23 and 22' are thus arranged to open to permit passage of liquid from the reservoir to the piston, ram and ram chambers, but will all seat and prevent the passage of liquid in the reverse direction. pumping operation, therefore, will cause liquid to be passed rapidly through the valve passages to the ram cylinder so as to cause a rapid projection of the ram under low pressure. During this movement the double-acting valve heads 29, 30 in the reversechannel C will close and open in opposite directions so as to prevent the passage of liquid therethrough.

Upon movement of the splaed lever into position high, the eccentric member 34 will move the controlling arm 31 against the action of the spring 32 to engage'the valve head 22 on the stem 22' so as to hold the valve head 22' 011 its seat and this entire double-acting valve is retained in inoperative position. Now upon a stroke of the piston in a forward direction, liquid will be passed through the valve heads 22 and 22 on the stem 22 and upon a reverse stroke, liquid will simply move past these valve heads in the reverse direction going back to the reservoir from which it came. Upon the forward jstroke, however, liquid also passes through the valve head 23 to the high pressure cylinder 11 and von the return stroke, this valve will close so as to permit a building up of pressure in said high pressure cylinder from which liquid will be forced through the .aeoaear speed lever may be moved to neutral, andthe hydraulic pressure released by sliding .pump lever 19 upwards in its socket as described hereinafter. The hydraulic closing pressure is released during the operation of filtration in order to release packings and valves of stress. The press may be pumped up in the conventional manner which need not here be described and the operation of filtration may be continued until completed.

When now the speed lever 32is moved to neutral, the-cam on the eccentric or cam member 34 will press the controlling sleeve 31 further rearwardly to move the .valve stem 22 a suficient distance to engage the valve stem 23 so as to unseat the valve head 23'. The movement of the cam 34 locks the controlling element in this position and both the high and low pressure bores or chambers will pass liquid back to the reservoir, but the valve head 24' still being seated, pressure will still be held in the ram cylinder. To release the pressure from the ram cylinder, the speed lever is left in neutral position while A the valve head 24' is raised by an engagement of the cross-head 15 with the controlling sleeve 31. For this purpose, it is necessary to give the head 15, greater movement, and to this end, the lever 19, which in its normal ram-projecting stroke engages a limiting element 19, is slipped .upwardly in its socket so as to have a movement beyond said limiting element 19'. This further movement ofthe lever 19 causes the head 15 to engage and further move the spring-pressed controlling sleeve 31 and to 'cause the said sleeve to further press the valve head 22 and move the stems 22, 23 and 24 to lift thevalve head 24' ofi' its seat, whereupon pressure in the ram cylinder is released and liquid will begin to flow back to the reservoir, the valve head 22 on the rear of the stem 22 being still open. Liquid from the ram cylinder will now come back quickly until the pressure is equalized in the-hydraulic system.

After the completion of filtration, it is desirable to open the press quickly. and by the use of my invention, I utilize the same hand-pump for withdrawing or retracting the ram. By first operating the pump while in high position to provide a slight forward projecting movement of the ram, I en'- able a ready release of the mechanical'lorlv,

ing device, and then a quick release of the hold them oif their seats.

hydraulic pressure by moving the speed lever to neutral, sliding pump lever 19 upwards in its socket and pulling back, causing crosshead 15 to unseat the valve head 24 as pre viously described, and then a movement of the valve mechanism into reverse position, and the operation of the pump while the valve mechanism is in such reverse position will cause the withdrawal or retraction of the ram into the cylinder.

To this end, the speed lever is now moved into position designated reverse, whereupon the cam member 34 will move the controlling sleeve 31 into its fully closed position shown in Fig. 3. In this position the controlling sleeve completely closes the inlet valve head 22* and also restrains all the other valve heads in the liquid passage C to Simultaneously, the controlling sleeve 31 presses against the valve member 30 on the stem 29 to move and retain the valve head 29 in. restrained position off its seat, but leaving the outlet valve head 30 open and free to seat. The rearward stroke of the piston then causes fluid to close the Valve head 30 and a pumping action causes this valve head to be opened and closed to draw fluid through the piston chamber 10 and fluid passage C from the ram cylinder. As the ram is packed so as to produce a fluid and air tight joint with its cylinder by the packing hereinabove described, a partial vacuum will thus be produced which causes a relatively speedy withdrawal or backward movement of the ram into its cylinder.

- In the preferred embodiment, I preferably screw-thread the periphery 7 e of said ram and mount thereon a free-running lock-nut 40 having a hand-wheel 41. When the ram is moved into fully-projected position by the hydraulic pump hereinabove described, the lock-nut may be moved into abutment with the stationary or fixed end of the ram-cylinder to lock the ram in its press-closing posi- 45 tion. I

It will be seen that I have thus provided an adjustable locking device which positively and eflectively locks the ram in extended position and causes the ram to perform the functions of a hydraulic ram and a screw ram and effectively and positively to retain the press against an opening movement or blowing out during the filtration process. It will also be understood that while the hydraulic pressure, such as furnished by a hand pump, is suitable for providing all the necessary pressure to force a press into closed position, such hydraulic pressure is incapable of maintaining the press in closed position against the force encountered in the operation of pumping up the press for filtration,

so that the use of my free-running nut 40 on the ram enables the temporary hydraulic pressure of the hand-operated hydraulic pump to be instantly converted into positive 1. Hydraulic devices for closing and open ing filter presses and other pressure-applying mechanisms embodying, in combination, a ram and a ram-cylinder, a hydraulic pump including piston mechanism, a dual system of valves, one part of said dual system forcausing the projection of the ram, and the other part for exhausting the liquid to retract the ram, said retracting part having a valve which is free to seat in opposite directions during the operation of the projecting system part, and means for restraining said valve to cause it to pass liquid in one direction only and simultaneously restraining valves of the ram-projecting part of the dual system to cause a reverse movement of the liquid by the piston mechanism and a retraction of the ram.

2. Hydraulic devices for closing and opening filter presses and other pressure-applying mechanisms embodying, in combination, two separable parts, one of which comprises a ram and ram-cylinder, and the other a hydraulic pump, and means for applying said two parts to a filter press so that a single unit is formed after assembly with support derived entirely from the frame of the filter press.

3. Hydraulic devices for closing and opening filter presses and other pressure-applying mechanisms embodying, the combination with the frame of a filter press having a rammounting hole, of a filter press-closing device composed of separable parts, one comprising a hydraulic pump and the other a cylinder andram, and means for assembling these parts together from opposite ends of the ram-mounting hole in said frame support and to produce a single unit after assembling.

In witness whereof, I have signed my name to the foregoin s ecification.

T MAS E. RAYMOND. 

